In the Linux kernel, the following vulnerability has been resolved:

tty: abort break signalling on hangup

The break ioctls can race with hangup and end up calling into a tty driver for a device that is already gone or powered down.

Drivers must handle this race, but TCSBRK and TCSBRKP should still be aborted to avoid calling back into the driver after a user-controlled timeout (possibly even after the tty has been reopened).

Note that drivers should disable any break state on shutdown so just return on hangup (calling break ctl() again is racy and will most likely fail for drivers handling the race).